1. Field of the Invention
This invention pertains generally to a mechanical distention device and methods, and more particularly to a mechanical distension device for manipulating hollow organ growth.
2. Description of Related Art
Short bowel syndrome (SBS), also known as short gut syndrome, occurs in patients with insufficient length of intestine to maintain normal digestion and absorption. In the US alone more than 100,000 patients suffer from this life threatening disease every year. SBS is a condition that results in malnutrition, malabsorption and dehydration due to loss of large amounts of intestinal tissue. Typically, symptoms appear with greater than 70% of small bowel loss, although this varies and often depends on the presence of an ileocecal valve. The most common causes of SBS in the pediatric population are necrotizing enterocolitis, intestinal atresias, volvulus and abdominal wall defects.
Currently, the treatment for SBS includes medical therapy with total parenteral nutrition to provide necessary nutrients and hydration, and surgical therapy to increase absorption capacity and decrease transit time.
Surgical treatment options for SBS include procedures that increase length, slow down transit time and intestinal transplantation. These procedures have thus far been met with limited success and are associated with significant complications. Hyperalimentation via the parenteral route remains the mainstay of treatment, but is associated with significant complications which include catheter related infections, liver failure and osteoporosis. In addition, the management of patients with SBS is associated with a significant financial burden, with the average cost of care for the first year of management averaging over $500,000 per patient and subsequently home care alone surpassing $100,000 dollars per patient annually.
Recently however, the concept of using mechanical force to lengthen intestinal tissue has been studied using a variety of tissue expander devices. Several methods of applying mechanical force to an intestinal segment have been developed, including repeated injections of saline solution, gradual advancement of a screw, and use of a hydraulic piston. Many of these methods require repeated interventions such as serial screw advancements or saline injections. In addition, all of these techniques incorporate a device that is at least partly outside the abdominal cavity, introducing risks such as dislodgement, damage to the exterior component, infection, fistula formation and increased inflammation and adhesions making potential re-implantation of isolated segments very difficult. Furthermore, because these devices deliver force in only one direction, the ability to lengthen intestinal segments is limited by the confines of the abdominal cavity.
Accordingly, an object of the present invention is a method to achieve intestinal lengthening using a completely internal device that does not require repeated interventions during the lengthening procedure. At least some of these objectives will be met in the description described herein.